Adapters including electro-magnetic attaching means for use with extruders

ABSTRACT

Adapters are disclosed for use with extruders and are provided with electro-magnetic means operable to quickly, easily and securely interconnect the die member and the adapter. Preferably, the adapter is also provided with additional electro-magnetic means operable to similarly connect the adapter to the head member which may itself be conventionally detachably attached to the barrel of the extruder.

United States Patent 1191 [11] 3,779,063 Gannon Dec. 18, 1973 ADAPTERSINCLUDING 3,545,044 12/1970 Rebouich 425/3 ELECTRO-MAGNETIC ATTACHINGMEANS FOR USE WITH EXTRUDERS Inventor: Mathew R. Gannon, 243 Park Ave.,

Revere, Mass.

[22] Filed: Feb. 2,1972

[21] Appl. No.: 222,930

[52] US. Cl 72/253, 72/467, 279/1 A, 279/1 M [51] Int. Cl B23b /22 [58]Field of Search 279/1 A, l M; 425/DIG. 33, DIG. 190; 269/8; 335/289;72/253, 467

[56] References Cited UNITED STATES PATENTS 3,022,994 2/l962 Eklund335/289 34 33 a? I 38 42A Primary Examiner-Charles W. Lanham AssistantExaminer-Robert M. Rogers Attorney-Abbott Spear [57] ABSTRACT Adaptersare disclosed for use with extruders and are provided withelectro-magnetic means operable to quickly, easily and securelyinterconnect the die memher and the adapter. Preferably, the adapter isalso provided with additional electro-magnetic means operable tosimilarly connect the adapter to the head member which may itself beconventionally detachably attached to the barrel of the extruder.

9 Claims, 4 Drawing Figures ADAPTERS: INCLUDING ELECTRO-MAGNETICATTACHING MEANS FOR USE WITH EXTRUDERS BACKGROUND OF THE INVENTION suchinterruptions are necessary, the length of time in preparing for thenext run is obviously important.

The head of a typical extruder includes a head member releasably clampedto the barrel of the extruder, an adapter secured to the head member bybolts extending lengthwise through the adapter and into the head member,and a die member bolted in a similar manner to the adapter. The adapterand the die member have axial passages, that of the adapter reducing thecross sectional area of the extrusion and usually imparting to it across sectional shape related to the final extrusion and that ofautomatically receive precise positioning and once the die membereffecting the final extrusion of a particular size and shape.

It is necessary, of course, that the ends of the axial passages of theadapter register with the proximate ends of the head member and the diemember. Where the major changes in shapesare to be made, both theadapter and the die member must be replaced and, when only the size ofthe extrusion is to be changed, only the die member needs to bereplaced. In either case, considerable production time is lost becausethe replacement part or parts must be precisely positioned and securelyanchored in place.

THE PRESENT INVENTION The general objective of the present invention isto provide an adapter for use with the head and die members of extrudersenabling the adapter to be quickly and accurately secured to or releasedfrom the head member, the die member to be as easily and as accuratelysecured to or released from the adapter member, or both the adapter andthe die member-to be so secured or released.

In accordance with the invention, this objective is attained byproviding that at least the end wall of the adapter against which thedie member is seated and preferably also the end wall of the adapter tobe seated against the head memberhave electromagnetic means operable,when energized to securely interlock the mutually engaged faces. Eachsuch electro-magnetic means is located inwardly of the appropriate oneof the adapter end walls which end wall has at least two radially spacedportions magnetic material insulated from each other by non-magneticmaterial and, except for the gap established by the non-magneticinsulation ma terial, defining a flux path, To complete the flux path,when an electro-magnetic means is energized, it is necessary that theend face of the member to be connected thereto be of magnetic materialand overlapsaid two radially spaced portions. See United States Pat. No.2,561,769. When a flux path is thus completed, the proximate end wall ofthe member is engagement with the appropriate end wall of the adapter issecurely locked thereto until the circuit to the associatedelectro-magnetic means is opened. By such means, either or both endwalls of the adapter may be quickly and easily secured to the proximateend wall of the appropriate member or members and be as quickly andeasily detached as replaced.

A particular objective of the invention, when electromagnetic means areprovided for both end walls of the adapter, is to employ a separatecircuit for each of them and, additionally, to provide each such circuitwith a rheostat.

Yet another objective of the invention is to provide for the mechanicalattachment of the adapter to the barrel in a manner that enables theadapter to be quickly connected thereto and held thereon should thepower fail or its circuit be accidentally opened.

THE PREFERRED EMBODIMENT OF THE INVENTION In the accompanying drawings,a preferred embodiment of the invention is shown of which:

FIG. 1 is a perspective view of an extruder head including anelectro-magnetic adapter;

FIG. 2 is a longitudinal section of the adapter with the electromagnetsshown somewhat schematically and connecting the adapter to the headmember and the die member to the adapter;

FIG. 3 is a view of one end of the adapter; and

FIG. 4 is a schematic view of the electro-magnets and their circuits.

A conventional extruder, generally indicated at 10, has means, generallyindicated at 11, to clamp the outwardly and rearwardly tapered flange 12of the head member 13 against the outwardly and forwardly tapered flange14 at the proximate end of the extruder barrel 15 with the proximateends of their bores 13A and 15A, respectively, of the same size and inregistry. The bore 13A is shown as tapering by steps towards its outletend. I

The clamping means 11 includes a lower pair of flange straddling andgripping jaws 16 interconnected at each end through an arm 17 and avertical bolt 18 by a pivot 19. An upper pair of flange straddling andgripping jaws 20 is connected at their outer ends by guides 21 slidablyreceiving the bolts 18 but held captive thereon as by nuts 22.

Each of a pair of arms 23 is connected to the extruder 10 by a pivot 24.The proximate ends of the pairs of arms 23 are interconnected by a pivot25 and the ends of one of said pairs have pivot-receiving slots 26permitting the arms 23 to be swung upwardly or downwardly to a limitedextent by means of the handles 27, one for each pair of arms 23 andmounted thereon.

Each pair of arms 23 has links 28 and 29 pivotally connected thereto onopposite sides of its supporting pivot 24, both links 28 pivotallyconnected to the upper pair of jaws 20 and each link 29 pivotallyconnected to an appropriate one of the arms 17..

The clamping means 1 1 are thus operable to draw the clamping jaws 16and 20 into and out of clamping relationship with the head flange 12 andthe barrel flange 14 and in said clamping relation, the head member 13is secured against the end of the barrel 15.

A die 30 has an axial passage whose distal portion 31 is of the crosssectional size and shape wanted for the extrusion. As it is necessary toreduce the cross sectional area of the extruded mass from thatestablished by the outlet end of the hea d passage 13A, an adapter,generally indicated at 32, is positioned between the head member 13 andthe die 30. The adapter 32 has an axial passage 32A, which may also butdoes not necessarily, taper forwardly and inwardly but which typicallyimparts to the plastic being extruded a shape related to that to beestablished by the die member 30. As shown, the rear portion 31A of theaxial passage of the die member 30 is rearwardly and outwardly taperedto merge with the proximate end of the adapter passage. It is thuspossible toprovide extrusions of different sizes but of the same shapeby substituting one die member for another with the substituted diehaving a passage of a different cross-sectional area and its rearportion having a shorter or longer tapered portion to vary, as required,the reduction in cross-sectional area of the material passing throughthe adapter 32.

In accordance with the invention, the adapter 32 has a central wall 33and end walls 34 and 35 with inner and outer spacers 36 and 37separating the end walls from the intermediate wall. The end walls areinterconnected through the outer spaces 37 and the intermediate wall 33by a series of bolts 38 and through the inner spacer 36 and theintermediate wall by a series of bolts 39. Each end wall has a circularseries of sections of magnetic material 40 separated from each other andfrom its inner and outer edge by non-magnetic boundary material 41, butin the plane thereof. It will be understood that at least the end wallsof the die and head members that are to be in contact with the end wallsof the adapter are of magnetic material.

A series of coils 42 each having a core member are housed within theadapter between each end wall and the intermediate wall 33 with eachcore supported by a section 40 and said intermediate wall. The coils andcores inwardly of the adapter end wall 34 are indicated at 42 and 43,respectively, and those inwardly of the adapter end wall 35 beingindicated at 42A and 43A, respectively. The coils 42 are in a circuit 44provided with a rheostat 45 and a switch 46 while the coils 42 are in alike circuit 44A also provided with a rheostat 45A and a switch 46A. Theintermediate wall 33 has channels 33A and 33B for the circuits 44 and44A, respectively. It will be apparent that when the coils areenergized, no effective flux path exists until the boundary material 41is bridged as it is when the end of the appropriate one of the members13, 31 is in face-to-face contact therewith.

The coils 42 and 42A have opposite effect when their circuits are closedso that when the coils 42A are energized with the adapter 32 seatedagainst the head member 13, the adapter member is secured thereto.Similarly, when the die member 30 is seated against the end wall 34 withthe circuit 44 closed, the die member 30 is securely attached to theadapter 32.

It is preferred that at least one bolt, the bolt 38A, passes completelythrough the adapter and into the head member 13 in order to ensure that,should the power fail or be turned off, the adapter could not drop. Thebolt 38A is also useful in attaching the adapter 32. The bolt 38A may bea loose fit in its pas sage to enable movement of the adapter 32 whensupported thereby.

In order to ensure that the adapter and the die member may be preciselypositioned with their axial passage in registry with each other and withthe axial passage of the head member 13, the adapter 32 and the headmember 13 have markers 32B and 138, respectively, corresponding ones ofwhich are in alignment when their axial passages are in registry and theadapter 32 and the die member 30 also have markers 32C and 30C,respectively, which are in alignment when their axial passages register.In this connection, it will be noted that the provision of rheostats inthe circuits enable the adapter to be connected to the head member andthe die member connected to the adapter but manually movable to ensurecorrect positioning before being securely anchored.

I claim:

1. An adapter for securing a die member to the head member of anextruder, both members of magnetic material, said adapter including endfaces, each provided with portions of magnetic material that areradially extending and spaced and insulated from each other, saidadapter having a passage between its end faces dimensioned to effectcommunication between the two members when interposed with one end faceof the adapter seated in a predetermined position against the headmember and the die member seated in a predetermined position against theother end face of the adapter, the magnetic portions of each face beingdimensioned and spaced to be overlapped by the member with which it isin face-to-face contact, and said adapter including electromagneticmeans for each end face arranged and disposed so that when both meansare then energized, the flux paths are completed through the appropriateportions and the adapter is magnetically secured to the head member andthe die member is magnetically held to the adapter.

2. The adapter of claim 1 in which each of the electromagnetic meansincludes a circuit, each circuit including a switch and a rheostat.

3. In combination, a first member having a face to be secured to thevertical face of a second member, at least one member being of magneticmaterial, the face of the other member with which the face of said onemember is to engage provided with portions of magnetic material that areradially extending and spaced and insulated from each other, saidmembers having passages between their end faces to be placed incommunication with each other when said faces are in mutual contact andin predetermined relative position, said magnetic portions beingdimensioned and spaced to be overlapped by the face of magnetic materialwhen seated thereagainst, and the member that does not have the magneticportions including electromagnetic means arranged and disposed so thatwhen said faces are in mutual contact and said means are energized fluxpaths are completed through said portions whereby the members aremagnetically held together, and a circuit including said electromagneticmeans and provided with a switch and a rheostat.

4. The adapter of claim 1 in which there are an end wall, anintermediate wall, and spacing means between said walls, and saidelectromagnetic means includes a series of coils between each end walland the intermediate wall and encircling said passage. I

5. The adapter of claim 4, and a circuit for each of the electromagneticmeans, and the intermediate wall has channels, each receiving portionsof the appropriate circuit.

6. The adapter of claim 1 and bolt means detachably connecting theadapter to the head member, the bolt means when not set up providing forlimited lateral movement of the adapter relative to the head member.

7. The adapter of claim 1 in which there are a pair of end walls, anintermediate wall, and spacing means between each end wall and saidintermediate wall providuse.

9. The adapter of claim 1 in which the adapter and die member eachinclude two markers arranged and disposed with corresponding markers inalignment when the adapter and die member are positioned for use.

1. An adapter for securing a die member to the head member of anextruder, both members of magnetic material, said adapter including endfaces, each provided with portions of magnetic material that areradially extending and spaced and insulated from each other, saidadapter having a passage between its end faces dimensioned to effectcommunication between the two members when interposed with one end faceof the adapter seated in a predetermined position against the headmember and the die member seated in a predetermined position against theother end face of the adapter, the magnetic portions of each face beingdimensioned and spaced to be overlapped by the member with which it isin face-to-face contact, and said adapter including electromagneticmeans for eAch end face arranged and disposed so that when both meansare then energized, the flux paths are completed through the appropriateportions and the adapter is magnetically secured to the head member andthe die member is magnetically held to the adapter.
 2. The adapter ofclaim 1 in which each of the electromagnetic means includes a circuit,each circuit including a switch and a rheostat.
 3. In combination, afirst member having a face to be secured to the vertical face of asecond member, at least one member being of magnetic material, the faceof the other member with which the face of said one member is to engageprovided with portions of magnetic material that are radially extendingand spaced and insulated from each other, said members having passagesbetween their end faces to be placed in communication with each otherwhen said faces are in mutual contact and in predetermined relativeposition, said magnetic portions being dimensioned and spaced to beoverlapped by the face of magnetic material when seated thereagainst,and the member that does not have the magnetic portions includingelectromagnetic means arranged and disposed so that when said faces arein mutual contact and said means are energized flux paths are completedthrough said portions whereby the members are magnetically heldtogether, and a circuit including said electromagnetic means andprovided with a switch and a rheostat.
 4. The adapter of claim 1 inwhich there are an end wall, an intermediate wall, and spacing meansbetween said walls, and said electromagnetic means includes a series ofcoils between each end wall and the intermediate wall and encirclingsaid passage.
 5. The adapter of claim 4, and a circuit for each of theelectromagnetic means, and the intermediate wall has channels, eachreceiving portions of the appropriate circuit.
 6. The adapter of claim 1and bolt means detachably connecting the adapter to the head member, thebolt means when not set up providing for limited lateral movement of theadapter relative to the head member.
 7. The adapter of claim 1 in whichthere are a pair of end walls, an intermediate wall, and spacing meansbetween each end wall and said intermediate wall providing axiallyspaced annular chambers and each of said electromagnetic means includesa series of coils encircling said passage and connected to at least oneof the walls defining its chamber.
 8. The adapter of claim 1 in whichthe adapter and the head member each include two marks arranged anddisposed with corresponding markers in alignment when the adapter andhead member are positioned for use.
 9. The adapter of claim 1 in whichthe adapter and die member each include two markers arranged anddisposed with corresponding markers in alignment when the adapter anddie member are positioned for use.